TXSquirrel

When my tuner first noted the fuel pressure issue, he already suggested bypassing the FPCM or installing an Aeromotive fuel pump controller. He did that for all the cars with aftermarket pump. I am just trying to keep my car as close to factory and use Nissan parts whenever I can, so it's just me with my way. That's why I'm running R35 injectors, which are still more than what the -9s can put out anyway. After looking at the diagram more, I'm guessing this 12v source actually runs through the ignition switch. So if I can get a confirmation that will be great. Nissan did that with headlight harness, not a real surprise if 30 years ago Nissan decided to run fuel pump 12v through ignition switch.

I finally got around to diagnose this issue in detail, and I am not sure what to make of what I discover. The FPCM is working fine, doing its thing by increasing voltage as engine load increases. The problem is with 12v source for the pump. I first measured the voltage at pump relay, and I was only getting 10.5v ignition on and 11.7v at idle, about 2v below battery voltage. Then I measured at the fuse, same issue. I tried the fuses next to pump, which are various lights, no problem at all, 12.5v with engine off and close to 14v with engine on. So what happened between power source and the fuse harness? How was it wired, straight off battery? Look at the electrical diagram it's not too clear to me. Looks like the EGT sensor is tee'd off the same source...?

Side question. Anyone knows what is the width and offset of the RS05RR wheels on Motive Garage's car?

My Nismo pump was purchased new from RHDJapan 3 years ago. Sounds like the consensus is that the Nismo pump is much more likely the culprit than the FPCM? Is there any way to test the FPCM? So if I'm to bypass the FPCM for direct feed, what gauge wire is recommended? And what's that little valve inside the tank for? I always wonder why it's there...

Hi folks, I would like to get some inputs on this issue with my R32 GTR... Car was on the dyno, the fuel pressure would rise to ~60psi no problem, stayed at ~60psi for about half a second then dropped to ~50psi, and then stayed at ~50psi until let go of throttle. Idle fuel pressure stable at 43psi. Made 315kw previously on 93 octane, now 275kw... Injector duty cycle at 108%, but AFR stable at ~11. A quick run down of parts: Nismo fuel pump, R35 injectors, R35 AFM, NZEFI resistor delete, brand new OEM FPR, Nistune, Garrett -9s. Is the Nismo pump running out...? Or could it be the pesky fuel pump control module...? What does the FPCM do anyway?

https://www.dsportmag.com/the-tech/rb26dett-building-blocks-which-rb26dett-block-is-right-for-you/?fbclid=IwAR2CwPxSFF3k6AN_WKf_aDbIeEl7jP-QODtAjq-PFnogv4Dii0PbHxYjNlk Here is another comparison focusing on wall thickness, but they did have an old N1 block.

I am considering sending my gearbox to Shep next year if I cannot find a good used unit. Will see how that goes.

I don't believe ShepTrans sells individual components, they only offer complete rebuild service to avoid warranty issues. I also believe the $1500 base level rebuild is done with only their own in house parts, the PPG stuff is an optional upgrade. And yes they are pretty big in the R35 realm, the shop that pulled my engine uses Shep for their 2000hp R35 build.

My goal is 350kw without e85, that's why I thought the 570cc would get the job done. I rarely drive mine and a full tank would last 2-3 months, so I can't really run e85. I also thought running R35 injectors with R35 AFMs should be a friendly combo to Nistune. Getting closer at 315kw during my last pull. Bought a 76mm Plazmaman but yet to install it, still waiting for my tuner's dyno to be repaired...

Are you running any cams? I'm still running factory air box, so maybe that's my problem. Or maybe because I'm running R35 injectors at factory fuel pressure. I read somewhere that R35 base fuel pressure is 1 bar higher and that's why it can get that much power out of 570cc. Not sure if that's true.

I got this divided charge pipe made not too long ago, if you are unsure about buying a whole intake piping kit. http://www.gtrusablog.com/2018/04/split-twin-turbo-pipes-by-alex.html This is what it looks like installed in mine.

That's a lot of power for -9's, especially only at 20psi. What other mods do you have?

Yeah the difference from 3000 to 5000 rpm is astonishing. My tuner made his pulls on stock R32 turbos, so with any decent aftermarket turbos the improvement should be more pronounced. He has actually pushed hard on those stock turbos and intends to blow them up as he has a pair of 2530 waiting to go on, but they are surprisingly tough.

I extracted more info out of him, really hope he doesn't mind me posting this. RPM across the top and load on the left. Question for you folks about how camshaft degree translates into cam gear degree. His HKS exhaust camshaft has a centerline of 110, and he gained across all RPM range by retarding his exhaust cam gear by 2 degrees. My Tomei has a centerline of 115, to get the same effect how should I adjust my cam gear?

My tuner just did some before and after pulls with HKS Vcam and shared on his Facebook. I would like to share that here for those thinking about Vcam. His car is still running on stock R32 turbos with steel turbine wheels. The pulls were done on E60 ethanol mix. https://www.facebook.com/houston.zauto/posts/1368728369930762